Propeller



. Y 1931- w. l. MILLER 1,814,175

PROPELLER Filed Nov. 28, 1928 Warn/rap Patented July 14, 1931 UNITEDSTATES PATENT OFFICE PROPELLER,

Application filed November 28, 1928. Serial No. 322,443.

This invention relates to improvements in propellers and moreparticularly to pro pellers for boats and marine vessels. One object isto provide a propeller that will 5 provide greater thrust and speed forthe volume of water delivered per revolution. A further object is toprovide a propeller wherein the centrifugal force is broken or convertedinto a longitudinal thrust thus 10 materially increasing the speed ofthe vehicle propelled.

A further object is to provide a propeller wherein the normal impact ofthe head waters against the propeller is broken or diminished and thedischarge water coming therefrom is straightened out or deprived of itswhirl or lateral thrust before it is released.

With the foregoing and other objects in view the invention consists inthe combination and arrangement of parts to be hereinafter fullydescribed, pointed out in the claims and illustrated in the accompanyingdrawings which form a part of this application for patent and in whichFig. 1 is a view of the propeller applied to the stern of a boat orvessel.

Fig. 2 is an enlaraged longitudinal sectional view through thepropeller.

Fig. 3 is a front end view of the propeller including a portion of thesupport therefor.

Fig. 4 is a fragmentary view of a slightly modified form of support andguide used when the ropeller is driven from the rear.

Like re erence characters denote corresponding parts throughout theseveral views.

The propeller comprises a tubular hou sing provided in its interior andat the ends thereof with support guides between which the rotary blade,or blades, is supported upon a shaft received for rotation in the saidguides which serve as bearings therefor, the forward support guidehaving blades so curved as to break the impact of the head watersagainst the blade and the rear support guide having blades reverselycurved with relation thereto to break the whirl and lateral thrust ofthe water as it is discharged from the blade.

Two or more blades of graduated helicoid type that completely encircle atapered shaft are provided. These blades, which may be either right orleft hand, are both of identical diameter at any point. The referencenumeral 1 denotes the tubular housing which tapers gradually from itsrelatively large forwar-d'end 2 and is supported by the web 3 at therear end of the vessel 4. Spaced inwardly from the forward end of thehousing is a stationary forward guide support comprising the vboss 5 forthe wings 6 which may be three, more or less, innumber, said wings beingsecured to the wall of the housing. Spacedinwardly from the rear orcontracted end of the housing in like manner is the rear guide supportcomprising the sleeve 7 for the wings 8 which are similar in number tothe wings 6 but are reversely curved with respect thereto, said, wings 8being likewise secured, to the wall of the housing. The sleeve 7 extendsbeyond the rear end of the housing and serves as a support for therudder 9, except in the case of side propellers and in this case thesleeve 7 has the propeller shaft 10- extending entirely therethrough,this shaft being driven either from the front or rear depending upon thelocation of the propeller relative to the bow or stern of the vessel.

The propeller shaft 10 extends through the boss 5 and into the sleeve ,7in the form shown in Fig. 2 and is operatively supported in saidmembers, said shaft having fast thereto the tapered hub 11 of the blades12, 13, said hub 11 being of smaller diameter atits forward than at itsrearward end, the ends of said blades being spaced from the boss andsleeve 5, 7. The blades are disposed substantially. at right angles totheir hub and shaft at their ends and therefrom they are coiled orcurved, the curvature depending upon the speed desired, the load, etc.The diameter of the blades is less at their ends thanat points in theirintermediate portions. The several wings 6 of the forward guidesupportare, at their forward ends parallel to the boss and shaft 5, 10 and asthey recede are curved gently in the direction of rotation of the blades12, 13 while the wings 8 are curved in the opposite direction.

v and straightened out by the action of the The water received in theforward end of the housing is guided or directed by the wings 6 againstthe forward end of the blades 12, 13. The same amount of water receivedat the forward end of the housing is, of course, delivered from the rearor contracted end thereof but due to the relatively smaller size of therear end the water is delivered at a materially greater speed than it isreceived. The taper of the hub 11 and the slan'tb'f the propeller bladesrelative "thereto tends to speed up the flow of water through the housing. The blades 12, 13 at the forward endof the hub are disposed at anangle something less than a right angle but as they recede their slantincreases and their angle with the hub diminishes. The water thrown bycentrifugal force against the wall of the housing is thrust rearwardlysubstantially parallel to the shaftlO and its whirl is further arrestedguide support wings 8 which are curved in a direction opposite to therotation of the blades 12, 13, d V

The relative speed with which the water is, thrust outwardly from thecontracted end of the housing materially increases the speed at whichthe vehicle is driven.

1 In a propeller, a rotary shaft, blades, fast thereupon, a tubulartapered. housing receiving' said blades, stationary support guidearranged insaid housing in advance of a b a a d recei ngs d ha ndstationary support guide at the rear of said blades arranged in saidhousing and receiving said shaft.

2'. In a propeller, a rotary shaft, bladesfast thereupon, a tubulartapered housing receiving saidblades, a stationary support guidearranged in said housing in advance of said blades and receiving saidshaft, said support guide comprising wings curved in a common direction,and a stationary support guide at the rear of said blades arranged insaidhousing and receiving said shaft, said support guide comprisingwings curved in a direction opposite to that of the first named wings.3. In a propeller, a rotary shaft, blades fast thereupon, atubulartapered housing enclosing said' blades, a stationary support guide insaid housing in advance of said blades and comprising portions curved inthe direction of rotation of said blades, said support guide receivingsaid rotary shaft,

and a seoond support guide in said housing at the rear of said bladesand comprising portions curved in a direction opposite tothe rotation ofsaid blades.

4. In a propeller, a rotary shaft, blades fast. thereupon, a tubulartapered housing enclosing said blades, a tapered hub common tosaidblades, the taper thereof being reverse to that of-said housing, astationary'support guide at one end of said blades comprising portionscurved in the direction of rotation of said blades, and a second supportguide at the rear of said blades comprising portions curved reversely tothe first support guide.

5. In a propeller, a rotary shaft, graduated helicoid blades fastthereupon, a tapered tubular housing enclosing said blades, means withinsaid housing immediately in advance of said blades for breaking theimpact there against of the incoming water, and means at the rear'o'fsaid-blades" within said housing for straightening out the dischargewater from said blades.

In testimony that I claim the foregoing as my own I have hereto afiixedmy signature.

WILLMAN I. MILLER.

